1. Field of the Invention
The present invention relates to molded plastic parts having one or more displaceable members integrally molded therewith and which are displaceable by rupturing a frangible web or webs which connects the displaceable member to the main body member. More particularly, the present invention is concerned with a molded plastic connector block of the type utilized to connect and initiate detonation signal transmission lines, the connector block including an integrally molded displaceable member.
2. Description of the Related Art
Connector blocks for blasting initiation systems are well-known in the art as exemplified by U.S. Pat. No. 5,171,935 of R. J. Michna et al, issued Dec. 15, 1992. That Patent discloses a connector block having a channel formed therein for receiving a low energy detonator and an arcuate slot within which one or more signal transmission lines are retained in signal transmission juxtaposition with the detonator.
European Patent Application 0 500 512 A2 of V. Lindqvist et al discloses a connector block for signal transmission lines which is of cylindrical configuration and, as disclosed at column 11, lines 16-20 and illustrated in FIG. 6A, provides a detonator compartment having a head portion 69 formed with a hole 70 therein for insertion of a locking part, not shown in the drawing, which serves to prevent axial withdrawal of the detonator.
Connector devices which include pins or other members which are integrally molded to the main body of the connector are shown in the prior art. For example, U.S. Pat. No. 3,349,706 to E. J. Schaumann, issued Oct. 31, 1967, shows a connector for positioning detonating fuse and a delay device in operative relationship to each other so that a detonation stimulus can be propagated from one to the other. The structure illustrated in the drawings of this Patent shows a body of thermoplastic material having a central tubular portion 1 and including tapered pins 4 integrally connected by a thin flexible web 5 to the main body as described at column 2, line 38 et seq. The thin connecting webs 5 retain the pins with the body but are flexible enough to enable the pin to be rotated and inserted into an aperture provided for the purpose. Similar construction is shown in U.S. Pat. No. 4,424,747 of M. E. Yunan, issued Jan. 10, 1984. As described at column 6, line 26 et seq, pins 22 and 23 are integrally connected to sections 1B and 1C of the connector 1 by thin flexible webs of plastic 24 and 25, respectively.
U.S. Pat. No. 4,248,152 to M. E. Yunan, issued Feb. 3, 1981, discloses an explosive booster capable of being connected to donor and receiving detonating cords which include a slotted locking means 21 which appears to have an integrally molded hinge to enable locking means 21 to be rotated to form a closure with slot 17 to lock a trunk-line in place. See FIG. 2 and column 5, lines 60-62.